Removal of metal ions and humic acid from water by iron-coated filter media

Fractionation of humic acid upon adsorption to goethite: Batch and column studies

“…This shape of BTC was also found during the transport of HA in iron-coated sand columns at pH 5.9-7.2 [35,36]. As reported by Lai and Chen [37], more than 95% and 80% of HA (10 and 20 mg/L) was still removed by goethite-coated sand at 60 PV at pH 3.5. As a result, goethite-coated sand is a potential adsorbent for HA (or NOM) removal from water, especially at normal and acidic conditions.…”

Effects of heavy metals and oxalate on the zeta potential of magnetite

“…Depending on pH and on type and concentration of organic ligands, mineral dissolution may or may not be enhanced, and metal adsorption by mineral surfaces may be suppressed or enhanced by the presence of ligands [53][54][55][56]. The presence of high-molecular-weight organic acids, such as humic acid, leads to increased adsorption of copper and lead [57]. However, it has been reported that the most effective method for intensifying the decontamination of clay soils from heavy metals is the wetting of soil with wetting reagents such as acetic acid, and the solubility of heavy metals and so the effectiveness of the electrokinetic remediation can be also enhanced by adding chelating or complexing agents such as citric acid and ethylenediaminetetraacetic acid [58].…”

Removal of 4-chlorophenol from aqueous solution by granular activated carbon/nanoscale zero valent iron based on Response Surface Modeling

“…The use of a support, like activated carbon, does have suitable porosity for absorption of 4-CP from water and prevents the agglomeration of iron and therefore presents a higher specifi c surface area and surface charge of iron to the aqueous stream (Ponder et al 2000). The characteristic contributes to extreme absorption of organic substances and heavy metals (Lai andChen 2001, Cheng et al 2005).…”